I had a headcanon about Au Ra horns posted in an older thread.
I imagine Au Ra horns to function similar to narwhal tusks: innervated sensory organs with nerve endings that connect stimuli to the brain. Following this, then other than hearing (which is the detection of vibrations made in the air) an Au Ra would be able to use these organs to sense changes in humidity and temperature, to a limited extent. Being more sensitive to sound in addition to sensing fluctuations in the air would be in line with the lore blurb that described Auri horns as giving them "enhanced spacial recognition"; the more you sense, the more you're aware of, if subconsciously.
As far as the surface, I think it'd be...well, matching their scales in texture. Tough, rough, and somewhat chitinous. These are large and prominent appendages, in sharp contrast to human ears which are small in relation to the head and typically flat. Au Ra horns by necessity would have to be hardened and reasonably durable, perhaps encased in a layer of hollow but tough bone or something similar.
That said, as far as evolution is concerned I'm pretty sure all Au Ra have roughly the same level of perception. Unless a group of Au Ra managed to be totally isolated in an extreme environment (for example, complete darkness) for an extended enough period of time for natural selection to kick in, I don't particularly think it's the case for different tribes of Au Ra to have different levels of sensory perception.
I imagine Au Ra horns to function similar to narwhal tusks: innervated sensory organs with nerve endings that connect stimuli to the brain. Following this, then other than hearing (which is the detection of vibrations made in the air) an Au Ra would be able to use these organs to sense changes in humidity and temperature, to a limited extent. Being more sensitive to sound in addition to sensing fluctuations in the air would be in line with the lore blurb that described Auri horns as giving them "enhanced spacial recognition"; the more you sense, the more you're aware of, if subconsciously.
As far as the surface, I think it'd be...well, matching their scales in texture. Tough, rough, and somewhat chitinous. These are large and prominent appendages, in sharp contrast to human ears which are small in relation to the head and typically flat. Au Ra horns by necessity would have to be hardened and reasonably durable, perhaps encased in a layer of hollow but tough bone or something similar.
That said, as far as evolution is concerned I'm pretty sure all Au Ra have roughly the same level of perception. Unless a group of Au Ra managed to be totally isolated in an extreme environment (for example, complete darkness) for an extended enough period of time for natural selection to kick in, I don't particularly think it's the case for different tribes of Au Ra to have different levels of sensory perception.
